实现Reapter控件数据导出功能

本质：将Reapter控件里的数据通过循环读取表头，标题，并将其以Html的形式写入到xls里面，实现导出功能！

后台代码：

protected void BtnExport_Click(object sender, EventArgs e)
{
using (TextWriter tw = new StringWriter())
{
using (HtmlTextWriter htw = new HtmlTextWriter(tw))
{
System.Text.StringBuilder s = new System.Text.StringBuilder();
s.AppendLine("<table style='width:800px;' border=1>");
HtmlTableRow trHeader = this.rpt_GridReport.Controls[0].FindControl("trTitle") as HtmlTableRow;

if (trHeader != null)
{
s.AppendLine("<tr>");
for (int a = 0; a < trHeader.Cells.Count; a++)
{
s.AppendFormat("<td><center>{0}</center></td>", trHeader.Cells[a].InnerText);
}
s.AppendLine("</tr>");
}

for (int i = 1; i <= this.rpt_GridReport.Items.Count; i++)
{

HtmlTableRow tr = this.rpt_GridReport.Controls[i].FindControl("trEval") as HtmlTableRow;
s.AppendLine("<tr>");
for (int j = 0; j < tr.Cells.Count; j++)
{
s.AppendFormat("<td><center>{0}</center></td>", tr.Cells[j].InnerText);
}
s.AppendLine("</tr>");
}

s.Append("</table>");
Export("application/ms-excel", "excel.xls", s.ToString());
}
}
}

private void Export(string FileType, string FileName, string s)
{
Response.Charset = "utf-8";
Response.ContentEncoding = System.Text.Encoding.UTF8;
Response.AppendHeader("Content-Disposition", "attachment;filename=" + HttpUtility.UrlEncode(FileName, System.Text.Encoding.UTF8).ToString());
Response.ContentType = FileType;
Response.Write(s);
Response.End();

}